Elenco Electronics EP-130, Руководство пользователя

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No, you cannot find the word NAND in your
dictionary (unless it is an electronics or computer
dictionary). This is a newly coined term that means
an inverted, or a Non-AND function. It produces
output conditions that are the opposite of the AND
circuit’s output conditions. The NAND output is low
when both inputs A and B are high. And the output
is high if either or both of the inputs are low. The
logic symbol looks like the AND symbol, but with a
small circle at the output. The function is
represented AB.
When either or both terminals, A and B are
connected to terminal 124 (the logic low terminal),
negative current flows through the diode(s) and the
NPN transistor stays off. The LED remains off. When
both inputs are connected to terminal 119 (the logic
high terminal), both diodes allow positive voltage to
flow through them. This positive voltage turns the
NPN transistor on, so that current flows to light L on
the LED.
Notes:
EXPERIMENT #29: DTL “NAND” CIRCUIT WITH LED DISPLAY
Wiring Sequence:
o
81-20-19-18-119
o
25-47
o
82-46-128-126
o
48-130
o
121-122
o
124-129
o
125-(to 124 “LOW” or 119 “HIGH”)
o
127-(to 124 “LOW” or 119 “HIGH”)
Schematic